There were sellers buying the smallest RAM units, changing the RAM chips, and then reselling them as the higher RAM SKUs. The sellers who do this don’t always care to use good RAM chips and may even use QA reject parts. When the unit doesn’t work correctly, the anger and RMA requests are directed back at the Raspberry Pi foundation.
The user friendly option would be to print the amount of RAM in very large letters on the PCB.
There happens to be a lot of suitable surface on the PCB to the right of the text "Raspberry Pi 5" on the PCB anyway (§). Right now the amount of RAM is hard to read and easy to modify (move a little tiny SMD resistor).
Drawback: You need different silkscreens for different amounts of RAM.
Btw, if you're worried about RAM-swapped units you can already verify them as described at <a href="https://geekworm.com/blogs/news/prevent-ram-swapped-raspberry-pi-5-how-to-verify-factory-ram-size" rel="nofollow">https://geekworm.com/blogs/news/prevent-ram-swapped-raspberr...
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(§) as can be seen here <a href="https://pip-assets.raspberrypi.com/categories/1129-pcn/documents/RP-006041-PC-2-PCN%20Raspberry%20Pi%205B%20Rev%204.pdf" rel="nofollow">https://pip-assets.raspberrypi.com/categories/1129-pcn/docum...
it can be very easily done by burning it with laser on prepared blank box on silkscreen - even iPhones are marked this way with their own serial numbers
the only reason why pis are not marked this way is because raspberry didn't wanted to (so far)
A little bit of acetone and a q-tip will remove the silkscreen, and then the PCB can easily re-marked by the scammer. Having a new silkscreen made is pocket change.
That's still trivial to defeat. They're very capable and determined. In the olden days they used to mill the top of microprocessor ie intel x86 to remove the engraving and engrave the fake label. These days I imagine it's way more advanced
One way of doing it... You can blast away the original markings / copper using laser and put something in place like sheet of copper or something that resembles copper, add solder mask layer on top. Done.
These operations are not hobbyist level, they have access to the machinery to make it trivial.
Put a sticker over it. Sure, the PCB says 2GB, the sticker says 8GB, it was sold as 8GB, how many buyers are going to dig in and really understand what's going on?
No, this is not sufficient, since it would still allow you to swap to shite ram of the same size. This is an age-old problem for counterfeits. The ink on the chip/PCB isn't worth anything. The only way to actually catch this is to do a IQC that runs a full RAM test and hope that if you can't see a difference in performance (throughput, BER, timings, etc), then the chip is correct, with a bit of periodic de-lidding for anything suspicious/sampled. Then, if you can afford it, you blacklist the vendors that are caught changing things.
They also added a bit of internal ink, which is worth just a little more:
> we now also program in some other device attributes, meaning that switching parts of the same size may not work.
Working with vendors in China is entirely adversarial (mostly because their supply chain is vulnerable too), at this scale.
Embedding it on the board won't work. Fraudsters are really good at doctoring chip and board makings nowadays, even below the solder mask. It's hard to imagine as a westerner, but the necessary equipment to do that kind of thing is trivially available in most of east Asia.
On-chip fuses would be a good solution. Which, of course, is already what they're using to lock chips to specific memory. There's just not a good reason to brick the board when the memory doesn't match. Have the firmware flash a warning on the screen before boot. Problem solved.
Aurornis · · focus · HN ↗
Tepix · · focus · HN ↗
Drawback: You need different silkscreens for different amounts of RAM.
Btw, if you're worried about RAM-swapped units you can already verify them as described at <a href="https://geekworm.com/blogs/news/prevent-ram-swapped-raspberry-pi-5-how-to-verify-factory-ram-size" rel="nofollow">https://geekworm.com/blogs/news/prevent-ram-swapped-raspberr...
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(§) as can be seen here <a href="https://pip-assets.raspberrypi.com/categories/1129-pcn/documents/RP-006041-PC-2-PCN%20Raspberry%20Pi%205B%20Rev%204.pdf" rel="nofollow">https://pip-assets.raspberrypi.com/categories/1129-pcn/docum...
kiicia · · focus · HN ↗
the only reason why pis are not marked this way is because raspberry didn't wanted to (so far)
buildsjets · · focus · HN ↗
jackyinger · · focus · HN ↗
hasperdi · · focus · HN ↗
unrented7977 · · focus · HN ↗
hasperdi · · focus · HN ↗
These operations are not hobbyist level, they have access to the machinery to make it trivial.
lightedman · · focus · HN ↗
It is so trivial anyone that's ever done fingernail polish can do it. The process is roughly the same.
brookst · · focus · HN ↗
nomel · · focus · HN ↗
They also added a bit of internal ink, which is worth just a little more:
> we now also program in some other device attributes, meaning that switching parts of the same size may not work.
Working with vendors in China is entirely adversarial (mostly because their supply chain is vulnerable too), at this scale.
ryukoposting · · focus · HN ↗
On-chip fuses would be a good solution. Which, of course, is already what they're using to lock chips to specific memory. There's just not a good reason to brick the board when the memory doesn't match. Have the firmware flash a warning on the screen before boot. Problem solved.